Sugar-free candies clean out your digestive system better than a giant pipe-cleaner. Not to put too fine a point on it, they make you poop. How do these ultra-laxatives work, and why are they still on the market?

Lycasin, Maltitol, and Gummy Bears

Reviewers on Amazon made Haribo Sugar Free Gummy Bears famous when they gave reviews testifying that the bears went into their body and out the other end at a break-neck run, taking everything else in their digestive system with them. The unhappy commenters mentioned stomach rumbles, ear-splittingly loud flatulence, and diarrhea. This is not confined to gummy bears. Any food loaded up with a low-calorie sugar called Lycasin will do the same.